<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        div{
            position: fixed;
            margin: auto;
            left: 0;top: 0;right: 0;bottom: 0;
            height: 400px;
            width: 400px;
        }
        div p{
            font-size: 50px;
        }
    </style>
</head>
<body>
    <div>
        <p>待完成页面</p>
        <button id="btn">回到首页</button>
    </div>
</body>
<script>
    var btn =document.getElementById('btn');
    btn.onclick=function(){
        location.href='./index.html';
    }
</script>
</html>